Explain any three aggregate functions with examples. Aggregate Functions are keywords in SQL used to manipulate values within columns for output purposes. A function is a command always used in conjunction with a column name or expression. Ther…

Explain Database architecture There are following three levels or layers of DBMS architecture: • External Level •Conceptual Level • Internal Level Objective of the Three Level Architecture The objective of the three level ar…

Explain the three levels in data abstraction. Explain the three levels in data abstraction. Three levels of data abstraction are: 1. Physical level : How the data is stored physically and where it is stored in database.…